Esophageal pH-impedance monitoring in patients with therapy-resistant reflux symptoms: 'on' or 'off' proton pump inhibitor?

Comparison of health care resource utilization and costs among patients with GERD on once-daily or twice-daily proton pump inhibitor therapy

BACKGROUND

The purpose of this study was to assess differences in health care resource utilization and costs associated with once-daily and twice-daily proton pump inhibitor (PPI) therapy. Most patients with gastroesophageal reflux disease (GERD) achieve symptom control on once-daily PPI therapy, but approximately 20%-30% require twice-daily dosing.

METHODS

Patients were ≥18 years of age with at least one medical claim for GERD and at least two PPI claims from HealthCore's Integrated Research Database (HIRD(SM)) during 2004-2009. Patients were continuously eligible for 12 months before and after the index date (date of first PPI claim). Based on PPI dosing throughout the post-index period (quantity of medication dispensed/number of days supply), patients were classified as once-daily (dose ≤ 1.5 pills per day) or twice-daily (≥1.5) PPI users.

RESULTS

The study cohort included 248,386 patients with GERD (mean age 52.8 ± 13.93 years, 56% females) of whom 90% were once-daily and 10% were twice-daily PPI users. The Deyo-Charlson Comorbidity Index for once-daily and twice-daily PPI users was 0.70 ± 1.37 and 0.89 ± 1.54, respectively (P < 0.05). More once-daily patients had claims for Barrett's esophagus (5% versus 2%, P < 0.0001) than twice-daily patients. Post-index, higher proportions of twice-daily patients had at least one GERD-related inpatient visit (7% versus 5%), outpatient visit (60% versus 49%), and office visit (48% versus 38%) versus once-daily patients (P < 0.0001). Mean total GERD-related health care costs were $2065 ± $6636 versus $3749 ± $11,081 for once-daily and twice-daily PPI users, respectively (P < 0.0001).

CONCLUSION

Patients receiving twice-daily PPI therapy were likely to have more comorbid conditions and greater health care utilization and overall costs compared with patients using once-daily PPI therapy.

Normal values of pharyngeal and esophageal 24-hour pH impedance in individuals on and off therapy and interobserver reproducibility

BACKGROUND & AIMS

Combined pH and impedance monitoring can detect all types of reflux episodes within the esophageal lumen and the pharynx. We performed a multicenter study to establish normal values of pharyngeal and esophageal pH-impedance monitoring in individuals on and off therapy and to determine the interobserver reproducibility of this technique.

METHODS

We collected ambulatory 24-hour pH-impedance recordings from 46 healthy subjects by using a bifurcated probe that allowed for detection of reflux events in the distal and proximal esophagus and pharynx. Data were collected when subjects had not received any medicine (off therapy) and after receiving 40 mg esomeprazole twice daily for 14 days (on therapy). The interobserver agreement for the detection of reflux events was determined in 20 subjects off and on therapy. Results were expressed as median (interquartile range).

RESULTS

Off therapy, subjects had a median of 32 reflux events (17-45) in the distal esophagus and 3 (1-6) in the proximal esophagus; they had none in the pharynx. On therapy, subjects had a median number of 21 reflux events (6-37) in the distal esophagus and 2 (0-5) in the proximal esophagus; again, there were none in the pharynx. Interobserver agreement was good for esophageal reflux events but poor for pharyngeal events.

CONCLUSIONS

We determined normal values of pharyngeal and gastroesophageal reflux events by 24-hour pH-impedance monitoring of subjects receiving or not receiving esomeprazole therapy. Analyses of esophageal events were reproducible, but analyses of pharyngeal events were not; this limitation should be taken into account in further studies.

Effect of proton pump inhibition on acid, weakly acid and weakly alkaline gastro-esophageal reflux in children

BACKGROUND

The effect of proton pump inhibitors on the characteristics of gastroesophageal reflux (GER) in children and adolescents was evaluated.

METHODS

Twenty-one children and adolescents with symptoms suggesting GER disease (GERD) underwent upper endoscopy and a 24-hour multichannel intraluminal impedance/pH (MII-pH) monitoring before and at the end of 2 months of therapy with proton pump inhibitors (PPIs).

RESULTS

Fourteen (67%) patients reported clinically relevant symptom improvement after 2 months of PPIs intake. At the first endoscopy, 8 (38%) patients had macroscopic signs of reflux esophagitis; after two months of therapy, 6/8 (75%) patients had a complete mucosal recovery. There was a significant reduction in the total percentage of mean acid reflux time (from 13.1% to 3.8%), and the De Meester score dropped to normal (from 46.4 to 13.1). The mean number of acid refluxes decreased significantly from 48 to 15 per 24 hours, while inversely, the mean number of weakly acid refluxes increased significantly from 26 to 64 per 24 hours. PPI therapy did not affect the total number of reflux episodes, the number of liquid and mixed refluxes, the duration of esophageal bolus exposure and proximal extent of the reflux.

CONCLUSIONS

In children and adolescents with GERD, PPIs do not affect the total number of reflux episodes. PPIs only decrease the acidity of refluxate. Nevertheless, the majority of patients with typical reflux symptoms may report symptom improvement. Esophagitis can be healed after PPI treatment. The treatment of weakly acid and weakly alkaline reflux remains a challenge for physicians in the future.

Prolonged 2-day esophageal pH-metry with impedance monitoring improves symptom-reflux association analysis

BACKGROUND

The day-to-day variability in the number of reflux episodes and symptoms of gastro-esophageal reflux disease is high; therefore, the assessment of reflux disease based on 24-h monitoring may be inaccurate.

AIMS

The aim of the study was to compare prolonged (48 h) and standard (24 h) pH-impedance monitoring (pH-MII).

METHODS

Fifty-four consecutive patients with typical and atypical reflux symptoms underwent 48-h pH-MII. Acid exposure time (AET), total number of reflux episodes (TR), number of symptoms, and symptom association probability (SAP) were analyzed after the first 24 h and compared with the results obtained during 48 h of monitoring.

RESULTS

The differences between the fractions of patients with normal and abnormal total AET and TR on both days were not significant. The percentage of patients with positive SAP was 57.9% at 24 h and 71.9% at 48 h (difference: 14.81%, 95% CI 0.7-21.29, P<0.05). There were ten patients (10/54, 18.5%) with positive SAP after 48 h that had been negative in the first 24 h. In comparison to 24 h monitoring, patients reported a significantly increased number of various symptoms correlated with reflux after 48 h.

CONCLUSIONS

Extending pH-MII monitoring to 48 h does not improve the detection of abnormal acid exposure. However, it does increase the fraction of patients with positive symptom-reflux association by as much as 18.5%.

Acid-suppressive therapy with esomeprazole for relief of unexplained chest pain in primary care: a randomized, double-blind, placebo-controlled trial

OBJECTIVES

High-quality data regarding the efficacy of acid-suppressive treatment for unexplained chest pain are lacking. The aim of this study was to evaluate the efficacy of esomeprazole in primary-care treatment of patients with unexplained chest pain stratified for frequency of reflux/regurgitation symptoms.

METHODS

Patients with a ≥ 2-week history of unexplained chest pain (unrelated to gastroesophageal reflux) who had at least moderate pain on ≥ 2 of the last 7 days were stratified by heartburn/regurgitation frequency (≤ 1 day/week (stratum 1) vs. ≥ 2 days/week (stratum 2)) and randomized to 4 weeks of double-blind treatment with twice-daily esomeprazole 40 mg or placebo. Chest pain relief during the last 7 days of treatment (≤ 1 day with minimal symptoms assessed daily using a 7-point scale) was analyzed by stratum in keeping with the predetermined analysis plan.

RESULTS

Overall, 599 patients (esomeprazole: 297, placebo: 302) were randomized. In stratum 1, more esomeprazole than placebo recipients achieved chest pain relief (38.7% vs. 25.5%; P=0.018); no between-treatment difference was observed in stratum 2 (27.2% vs. 24.2%; P=0.54). However, esomeprazole was superior to placebo in a post-hoc analysis of the whole study population (combined strata; 33.1% vs. 24.9%; P=0.035).

CONCLUSIONS

A 4-week course of high-dose esomeprazole provided statistically significant relief of unexplained chest pain in primary-care patients who experienced infrequent or no heartburn/regurgitation, but there was no such significant reduction in patients with more frequent reflux symptoms.

Clinical applications of esophageal impedance monitoring and high-resolution manometry

Esophageal impedance monitoring and high-resolution manometry (HRM) are useful tools in the diagnostic work-up of patients with upper gastrointestinal complaints. Impedance monitoring increases the diagnostic yield for gastroesophageal reflux disease in adults and children and has become the gold standard in the diagnostic work-up of reflux symptoms. Its role in the work-up for belching disorders and rumination seems promising. HRM is superior to other diagnostic tools for the evaluation of achalasia and contributes to a more specific classification of esophageal disorders in patients with non-obstructive dysphagia. The role of HRM in patients with dysphagia after laparoscopic placement of an adjustable gastric band seems promising. Future studies will further determine the clinical implications of the new insights which have been acquired with these techniques. This review aims to describe the clinical applications of impedance monitoring and HRM.

Increased frequency and enhanced perception of reflux in non-erosive reflux disease patients non-responders to proton pump inhibitors

BACKGROUND

The unsatisfactory response to medical treatment in non-erosive patients is becoming a real challenge for gastroenterologists. Non-responder patients, evaluated under treatment, present symptoms which are related to non-acidic, mixed and proximal reflux episodes.

METHODS

To elucidate the reflux pattern and mechanisms related to persistence of symptoms despite treatment, oesophageal pH-impedance was performed in 55 non-erosive responder and 24 non-responder patients, studied off therapy. Ten responder and 10 non-responder patients underwent a repeated study during proton pump inhibitor treatment.

RESULTS

Non-responders were characterised by a higher overall number and larger proportion of symptomatic reflux episodes. Non-responders were also characterised by an enhanced sensitivity to acidic, mixed and proximal refluxes. Weakly acidic reflux accounted for 29% of symptomatic refluxes in non-responders and 34% in responders. Proportions of acidic and weakly acidic reflux episodes were comparable both in responders and non-responders when analysed off and on treatment.

CONCLUSIONS

An increased overall number of reflux episodes and enhanced sensitivity to reflux are strongly associated with treatment failure. Treatment strategies aimed at decreasing transient lower oesophageal sphincter relaxations, pain modulators or anti-reflux surgery should be considered in non-responders in whom a significant relationship between symptoms and reflux has been confirmed.

The impact of reflux burden on Pseudomonas positivity in children with cystic fibrosis

OBJECTIVES

Nonacid gastroesophageal reflux (GER), particularly in patients taking acid suppression, has been implicated as a cause of respiratory infections. We hypothesize that children with cystic fibrosis (CF) and a higher nonacid reflux burden have greater rates of Pseudomonas aeruginosa (Pa) infection than patients with a lower reflux burden.

STUDY DESIGN

We reviewed the multichannel intraluminal impedance (pH-MII) tracings of 35 patients with CF between 2003 and 2010. We compared the reflux profiles between those patients who were Pa positive and Pa negative.

RESULTS

The mean age was 13.5 ± 5.8 years. Twenty-seven patients (76%) were Pa positive. Ninety seven percent of patients were taking proton pump inhibitors during pH-MII testing. The mean percentage of time pH was <4 was 8.5 ± 12%. Pa patients had a significantly higher total, acid and proximal nonacid reflux burden (P < 0.009). There was a negative correlation between nonacid reflux burden and FEV1 (r = -0.397, P = 0.03) and between total number of reflux events and FEV1 (r = -0.474, P = 0.009). After adjusting for age and FEV1, total reflux burden remains significantly associated with Pa positivity (P = 0.055).

CONCLUSIONS

Increased reflux burden may predispose patients to Pa infection and worse lung function.

Oesophageal sensation in response to high PCO(2) and acidic solutions in nonerosive reflux disease

BACKGROUND

Heartburn is commonly associated with the presence of acid in the oesophageal lumen. However, in patients with nonerosive reflux disease (NERD), the mechanism by which acid traverses the mucosa is not clear. We hypothesized that the luminal acid signal traverses the oesophageal epithelium in the form of the highly permeant gas CO(2) , which then is reconverted to H(+) in the submucosa.

MATERIALS AND METHODS

  Ten patients with heartburn, normal upper endoscopy and increased oesophageal acid exposure (NERD patients) and 10 healthy subjects were enrolled. Perceptual responses to intraoesophageal acid (0·1 N HCl solution) and a high PCO(2) solution were determined using a randomized cross over design. Stimulus-response functions to perfusions were quantified by three parameters: lag time to symptom perception, intensity rating and perfusion sensitivity score.

RESULTS

 In NERD patients, the difference in lag time to typical symptom perception, intensity rating and perfusion sensitivity score between high PCO(2) and acid perfusions was statistically significant (P = 0·02, 0·01 and 0·02, respectively). However, the difference in the same perfusion parameters between acid and high PCO(2) perfusions was nonsignificant in healthy controls. When NERD and controls were compared, the difference between the different perfusion variables was nonsignificant (adjusted to age).

CONCLUSIONS

In NERD subjects, acid perfusion reliably evoked heartburn symptoms of greater intensity than in healthy controls. Nevertheless, a high PCO(2) perfusion failed to produce symptoms in either group.

The added value of quantitative analysis of on-therapy impedance-pH parameters in distinguishing refractory non-erosive reflux disease from functional heartburn

BACKGROUND

By analysis of symptom-reflux association, endoscopy-negative refractory heartburn can be related to acid/non-acid refluxes with impedance-pH monitoring. Unfortunately, patients frequently do not report symptoms during the test. We aimed to assess the contribution of quantitative analysis of impedance-pH parameters added to symptom-reflux association in evaluating patients with endoscopy-negative heartburn refractory to high-dose proton pump inhibitor therapy.

METHODS

The symptom association probability (SAP), the symptom index (SI), the esophageal acid exposure time and the number of distal and proximal refluxes were assessed at on-therapy impedance-pH monitoring. Relationships with hiatal hernia and manometric findings were also evaluated.

KEY RESULTS

Eighty patients were prospectively studied. Refractory heartburn was more frequently related to reflux by a positive SAP/SI and/or abnormal impedance-pH parameters (52/80 cases) (65%) than by a positive SAP/SI only (38/80 cases) (47%) (P = 0.038). In patients with refractory non-erosive reflux disease (NERD) defined by a positive SAP/SI and/or abnormal impedance-pH parameters, the prevalence of hiatal hernia was significantly higher (56%vs 21%, P = 0.007) and the mean lower esophageal sphincter tone was significantly lower (18.7 vs 25.8 mmHg, P = 0.005) than in those (35%) with reflux-unrelated, i.e., functional heartburn (FH). On the contrary, no significant difference was observed subdividing patients according to a positive SAP/SI only.

CONCLUSIONS & INFERENCES

Quantitative analysis of impedance-pH parameters added to symptom-reflux association allows a subdivision of refractory-heartburn patients into refractory NERD and FH which is substantiated by pathophysiological findings and which restricts the diagnosis of FH to one third of cases.

Significance and degree of reflux in patients with primary extraesophageal symptoms

OBJECTIVES/HYPOTHESIS

Patients with extraesophageal symptoms are often suspected of having gastroesophageal reflux disease (GERD). However, the true prevalence and severity of reflux disease is not well studied. In this group of patients, the objectives of our study were to determine the prevalence and severity of esophageal acid exposure and classify the endoscopic findings.

STUDY DESIGN

Prospective cohort study.

METHODS

One hundred twenty-eight patients with extraesophageal symptoms underwent 48 hours of Bravo pH monitoring. Percent of time that pH was <4 (total upright and supine) was measured. Severity of reflux was categorized by the percent of total time pH was <4, with mild = >4.2% but <10%, moderate = 10% to 20%, and severe>20%. Endoscopic signs of esophagitis and Barrett's esophagus were determined.

RESULTS

There were 104/128 (81%) patients who had abnormal esophageal acid exposure, 44% in the upright and supine position, 38% in the upright position only, and 18% in the supine position only. There were 59/128 (46%) patients with mild reflux, 40/128 (31%) with moderate, and only 5/128 (4%) patients with severe reflux. 23/128 (18%) patients had evidence of esophagitis. Only 1/128 (0.8%) patients had pathologic Barrett's esophagus. Prevalence of abnormal esophageal acid exposure was similar in those with (75%) or without (66%) concomitant heartburn and/or regurgitation (P = .3).

CONCLUSIONS

Abnormal esophageal pH is common in patients with extraesophageal symptoms. Most have only mild (46%) to moderate (31%) reflux with a low prevalence of esophagitis (18%) or Barrett's esophagus (0.8%). The degree of esophageal acid reflux cannot be predicted from baseline presence or absence of typical GERD symptoms.

Chronic cough and esomeprazole: a double-blind placebo-controlled parallel study

BACKGROUND AND OBJECTIVE

Gastro-oesophageal reflux has been implicated in the pathogenesis of chronic cough. Guidelines on management suggest a therapeutic trial of anti-reflux medication. Esomeprazole is a proton pump inhibitor licensed for the long-term treatment of acid reflux in adults and we compared the effects of esomeprazole and placebo on patients with chronic cough.

METHODS

This was a prospective, single-centre, randomized, double-blind, placebo-controlled, parallel group study conducted over 8weeks. Fifty adult non-smokers with chronic cough and normal spirometry were randomized. Patients completed cough-related quality-of-life and symptom questionnaires and subjective scores of cough frequency and severity at the beginning and end of the study. They also kept a daily diary of symptom scores. Citric acid cough challenge and laryngoscopic examination were performed at baseline and the end of the study. The primary outcome was improvement in cough score.

RESULTS

There were no differences in cough scores in the placebo and treatment arms of the study although some significant improvements were noted when compared to baseline. In the cough diary scores there was a trend towards greater improvement in the treatment arm in patients with dyspepsia.

CONCLUSIONS

Esomeprazole did not have a clinically important effect greater than placebo in patients with cough. It suggests a marked placebo effect in the treatment of cough.

Extraesophageal gastroesophageal reflux disease (GERD) symptoms are not more frequently associated with proximal esophageal reflux than typical GERD symptoms

Extraesophageal (EE) symptoms such as cough and throat clearing are common in patients referred for reflux testing, but are less commonly associated with gastroesophageal reflux disease (GERD). Patients with reflux associated EE symptoms often lack typical GERD symptoms of heartburn and regurgitation. Our aim was to compare the frequency of proximal esophageal reflux between esophageal (typical) symptoms and EE (atypical) symptoms. Combined multichannel intraluminal impedance-pH (MII-pH) tracings were blinded by an investigator so that symptom markers were relabeled with a number without disclosure of symptom type. We selected 40 patients with at least five reflux-related symptom events for one of four symptoms (heartburn, regurgitation, cough, or throat clearing). A blinded investigator analyzed all 200 reflux episodes, reporting the proximal esophageal extent of the reflux for all symptoms. The percentage of symptom-related reflux extending proximally to 17 cm above the LES was similar among all four symptom types. At least 50% of all symptoms were associated with proximal esophageal reflux to 17 cm, with regurgitation having the highest frequency at 60%. Our data indicate that EE symptoms are not more frequently associated with proximal esophageal reflux than typical esophageal symptoms.

Wireless ambulatory pH studies: manometric or endoscopic guidance?

Wireless pH studies are widely used to assess the presence and severity of gastroesophageal reflux disease. We hypothesized that sedation or air insufflation during a preceding endoscopy may systematically alter results. A retrospective review of ambulatory pH studies completed between January 2008 and April 2010 was performed. The pH capsule was placed 6 cm above the endoscopically determined location of the squamocolumnar junction or 5 cm above the manometrically localized upper border of the lower esophageal sphincter (LES). A total of 356 patients (65% women) underwent pH studies using the BRAVO system (GIVEN Imaging, Yoqneam, Israel). In 186 patients (E-P), the capsule was placed during endoscopy. In 170 patients (M-P), capsule placement was based on manometric determination of LES boundaries using pharyngeal anesthesia only. Endoscopic placement was successful in all cases, whereas two patients could not tolerate capsule insertion with topical anesthesia only. The mean recording time did not differ between the two groups (E-P: 2468 ± 38 min; M-P: 2415 ± 40 min). The number of patients with abnormal findings on day 1 but normal results for day 2 was similar with 15% for E-P compared with 11% for M-P. However, there was a significant difference in total acid exposure times between days 1 and 2 for endoscopically (day 1: 7.3 ± 1.2; day 2: 4.8 ± 0.5; P < 0.01), but not manometrically based placement (day 1: 7.7 ± 0.7; day 2: 7.2 ± 0.6). There was no difference in the number of symptoms between days or groups (E-P day 1:13.4 ± 1.3; E-P day 2: 16.0 ± 1.6; M-P day 1: 14.1 ± 2.1; M-P day 2: 15.7 ± 2.0). Similarly, the symptom sensitivity index did not differ significantly between days and groups (E-P: day 1: 4.1 ± 0.5; day 2: 5.9 ± 0.8; M-P: day 5.3 ± 0.8; day 2: 5.7 ± 0.8). The majority of patients tolerate insertion of a wireless pH monitoring capsule without sedation. Unsedated placement did not negatively affect total recording times. Although endoscopy resulted in higher acid exposure on day one it did not significantly increase the overall fraction of abnormal tests. If confirmed in prospective studies, the more consistent findings and a potential to lower cost favor manometrically guided capsule placement.

In vitro effect of pantoprazole on lower esophageal sphincter tone in rats

AIM: To investigate the in vitro effects of pantoprazole on rat lower esophageal sphincter (LES) tone.

METHODS: Rats weighing 250-300 g, provided by the Yeditepe University Experimental Research Center (YÜDETAM), were used throughout the study. They were anesthetized before decapitation. LES tissues whose mucosal lining were removed were placed in a standard 30-mL organ bath with a modified Krebs solution and continuously aerated with 95% oxygen-5% carbon dioxide gas mixture and kept at room temperature. The tissues were allowed to stabilize for 60 min. Subsequently, the contractile response to 10^-6 mol/L carbachol was obtained. Different concentrations of freshly prepared pantoprazole were added directly to the tissue bath to generate cumulative concentrations of 5 × 10^-6 mol/L, 5 × 10^-5 mol/L, and 1.5 × 10^-4 mol/L. Activities were recorded on an online computer via a 4-channel transducer data acquisition system using the software BSL PRO v 3.7, which also analyzed the data.

RESULTS: Pantoprazole at 5 × 10^-6 mol/L caused a small, but statistically insignificant, relaxation in the carbachol-contracted LES (2.23% vs 3.95%). The 5 × 10^-5 mol/L concentration, however, caused a significant relaxation of 10.47% compared with the control. 1.5 × 10^-4 mol/L concentration of pantoprazol caused a 19.89% relaxation in the carbachol contracted LES (P < 0.001).

CONCLUSION: This is the first study to demonstrate that pantoprazole has a relaxing effect in isolated LESs. These results might have significant clinical implications for the subset of patients using proton pump inhibitors who do not receive full symptomatic alleviation from gastroesophageal reflux disease.

Esophageal acid exposure decreases intraluminal baseline impedance levels

OBJECTIVES

Intraluminal baseline impedance levels are determined by the conductivity of the esophageal wall and can be decreased in gastroesophageal reflux disease (GERD) patients. The aim of this study was to investigate the baseline impedance in GERD patients, on and off proton pump inhibitor (PPI), and in healthy controls.

METHODS

Ambulatory 24-h pH-impedance monitoring was performed in (i) 24 GERD patients with and 24 without pathological esophageal acid exposure as well as in 10 healthy controls and in (ii) 20 patients with refractory GERD symptoms despite PPI, once on PPI and once off PPI. Baseline impedance levels in the most distal and the most proximal impedance channels were assessed.

RESULTS

Median (interquartile range) distal baseline impedance in patients with physiological (2,090 (1,537-2,547) Ω) and pathological (781 (612-1,137) Ω) acid exposure was lower than in controls (2,827 (2,127-3,270) Ω, P<0.05 and P<0.001). A negative correlation between 24-h acid exposure time and baseline impedance was observed (r=-0.7, P<0.001). In patients measured off and on PPI, median distal baseline impedance off PPI was significantly lower than on PPI (886 (716-1,354) vs. 1,372 (961-1,955) Ω, P<0.05) and distal baseline impedance in these groups was significantly lower than in healthy controls (P<0.05 and P<0.001). Proximal baseline impedance did not differ significantly between the patients off PPI and on PPI (1,793 (1,384-2,489) vs. 1,893 (1,610-2,561) Ω); however, baseline impedance values in both measurements were significantly lower than in healthy controls (3,648 (2,815-3,932) Ω, both P<0.001).

CONCLUSIONS

These findings suggest that baseline impedance is related to esophageal acid exposure and could be a marker of reflux-induced changes to the esophageal mucosa.

Gastroesophageal reflux disease--from reflux episodes to mucosal inflammation

Gastroesophageal reflux disease (GERD) affects 20-30% of the population in Western countries, and is one of the most common clinical problems in daily practice. GERD-associated functional and structural abnormalities are caused by recurrent exposure of the esophagus to acidic and nonacidic refluxate of gastric contents (containing duodenal and intestinal proteases as well as acid and gastric pepsin) from the stomach. Major progress has been made in the understanding of the molecular pathogenesis of GERD-associated mucosal inflammation, suggesting a complex and multifactorial pathogenesis and immune-mediated effects. This Review summarizes the complexity of mucosal pathogenesis, including microscopic changes, mucosal inflammation and GERD-specific molecular mediators, in the context of the clinical features and pathophysiological characteristics of GERD. The abnormal exposure of the esophagus to luminal contents leads to chronic mucosal inflammation that is characterized by the release of IL-8 specifically, as well as other proinflammatory mediators, from the esophageal mucosa. Evidence from animal studies indicates a stepwise inflammatory response by the epithelium, which attracts immune effector cells to infiltrate the mucosa. From bench to bedside, these novel molecular findings might provide new treatment options beyond current acid-suppressive therapy and the principle of inhibition of transient lower esophageal sphincter relaxation.

Testing for gastroesophageal reflux in the 21st century

The following on testing for gastroesophageal reflux in the 21st century contains commentaries on wireless pH monitoring; extension of pH recording duration to 48 or 96 h; extraesophageal GERD syndromes, diagnosis paradigms, and related investigating tools; off- or on-PPI reflux monitoring in the preoperative setting; and the potential influence of PPIs on reflux parameters.

Direct measurement of gastroesophageal reflux episodes in patients with squamous cell carcinoma by 24-h pH-impedance monitoring

OBJECTIVES

Recent studies have consistently reported a significant association between gastric atrophy and esophageal squamous cell carcinomas (ESCCs). However, causative factors responsible for the linkage remain to be clarified. Multichannel intraluminal impedance monitoring in conjunction with a pH sensor (MII-pH) is a reliable technique to evaluate gastroesophageal reflux (GER) episodes, independent of the acidity. We investigated the potential roles of GER in the pathogenesis of ESCC with MII-pH.

METHODS

From August 2008 to May 2010, 14 consecutive inpatients with superficial ESCCs (ESCC group) and 14 age- and sex-matched inpatients without any esophageal dysplastic lesions (non-ESCC group) were enrolled. Twenty-four hour portable MII-pH monitoring was performed under standard hospitalized conditions. The data of MII-pH were used to identify acid reflux (AR: pH drop below 4.0 during a reflux episode) and non-AR (NAR: pH drop above 4.0 during a reflux episode).

RESULTS

The median intragastric pH of the ESCC group was 4.7 (2.3-6.4), implying hypochlorhydria in this patient group. The numbers of total reflux and NAR episodes in the ESCC group were significantly higher than those in the non-ESCC group (56 (43-87) vs. 35.5 (18-47), P=0.016 for total reflux and 46.5 (32-84) vs. 24.5 (8-37), P=0.012 for NAR), whereas the numbers of AR were similar in both groups. In addition, there was significance in the category of percentage time of bolus reflux episodes.

CONCLUSIONS

Using MII-pH monitoring, we revealed the clinical significance of GER, especially NAR, in ESCCs. NAR may be a key factor in the link between gastric atrophy and ESCCs.

Caution about overinterpretation of symptom indexes in reflux monitoring for refractory gastroesophageal reflux disease

BACKGROUND & AIMS

Symptom index (SI) and symptom association probability (SAP) are indexes used to analyze data collected from ambulatory pH and/or impedance monitoring and quantify the association between symptoms and reflux events. However, their characteristics are not well defined. We measured factors that affect SI and SAP values to determine their utility in assessing patients with refractory gastroesophageal reflux disease (GERD).

METHODS

We conducted a cross-sectional study of 254 patients with poor responses to proton pump inhibitor (PPI) therapy. Participants underwent esophagogastroduodenoscopy and wireless pH (n = 127) or impedance/pH monitoring when they were not receiving PPI therapy (n = 41) or impedance/pH monitoring while they received twice-daily PPI therapy (n = 86). SI and SAP values were calculated individually; ranges of values for each cell in the 2 × 2 contingency table were determined. Monte Carlo simulation was conducted to determine how varying reflux and symptom rates within the contingency table impacted the expected value and variability in SI and SAP.

RESULTS

At best, only 33% of patients who were refractory to PPI therapy had positive SI or SAP scores for acid or nonacid reflux events. Abnormal SAP (>95%) and SI (>50%) scores required high rates of reflux. At reflux rates less than 10%, observed in 70% of the studied population, SI and SAP values were largely determined by chance occurrences, rather than the relationship between symptoms and reflux. The values for each index varied significantly day-to-day.

CONCLUSIONS

SI or SAP indexes can be overinterpreted, unless patients with gastroesophageal reflux disease who are refractory to PPI therapy have high rates of reflux.

A prospective study to compare a symptom-based reflux disease questionnaire to 48-h wireless pH monitoring for the identification of gastroesophageal reflux (revised 2-26-11)

OBJECTIVES

The gastroesophageal reflux disease questionnaire (GerdQ) is a validated questionnaire that identifies patients with gastroesophageal reflux disease (GERD). The aim of this study was to prospectively evaluate the association between GerdQ scores and 48-h wireless pH recording in patients studied either on or off acid suppression.

METHODS

Demographics, symptoms, acid suppressant use, and GerdQ scores were obtained from consecutive patients referred for wireless pH testing; 48-h pH data and endoscopic findings were recorded. Multivariate logistic regression models controlling for age, gender, and body mass index (BMI) were used to evaluate the association between GerdQ scores, acid reflux, and symptom association probability (SAP) scores.

RESULTS

Wireless pH-metry was completed in 180 patients off proton pump inhibitor (PPI) (mean (s.d.) age, 50 (14) years; BMI, 28.08 (6.87) kg/m(2)) and 178 patients on PPI (mean (s.d.) age, 52 (14) years; BMI, 29.00 (6.90) kg/m(2)). Abnormal acid exposure was noted in 26% of patients on and 61% off PPI therapy. The odds of an abnormal study were 5.04 (95% confidence interval (CI), 3.14-8.11) times greater in patients studied off PPI therapy compared with patients studied on PPI therapy. The odds ratio of the SAP being >95% was 5.69 (95% CI, 3.36-9.64; P<0.001) for patients studied off PPI therapy compared with on PPI therapy. The mean (s.d.) GerdQ score was 7.48 (4.53) in patients on PPI therapy and 9.11 (1.25) in patients off PPI therapy (P<0.001). The odds of having an abnormal pH study was 1.08 (95% CI, 0.99-1.16; P=0.07) in patients studied off PPI therapy and 1.00 (95% CI, 0.92-1.08; P=0.94) in patients on PPI therapy for each point increase on the GerdQ. The odds of an abnormal SAP 95% in patients studied off PPI therapy was 1.18 (95% CI, 1.09-1.28; P<0.001) and 1.10 (95% CI, 1.01-1.21; P<0.03) in patients studied on PPI therapy for each point increase in the GerdQ score.

CONCLUSIONS

Higher GerdQ scores were predictive of an abnormal pH study in patients studied off PPI therapy. Compared with wireless pH capsule monitoring, the GerdQ has only modest sensitivity and specificity at diagnosing acid reflux and thus cannot be recommended as a screening tool for GERD.

Response of regurgitation to proton pump inhibitor therapy in clinical trials of gastroesophageal reflux disease

OBJECTIVES

The typical symptoms of gastroesophageal reflux disease (GERD) are heartburn and regurgitation. Extensive analysis has characterized heartburn and its responsiveness to proton pump inhibitor (PPI) therapy, but regurgitation has received relatively little attention. This study aimed to evaluate the response of regurgitation to PPI therapy in GERD trials.

METHODS

Studies were identified by systematic searches in PubMed and Embase, as well as searching congress abstracts and the reference lists of Cochrane reviews.

RESULTS

Regurgitation was not an entry criterion or the primary end point in any of the 31 clinical trials reporting the response of regurgitation to PPI treatment in GERD. The definitions of regurgitation and responsiveness varied among trials and over half used investigator assessment of response. Owing to these inconsistencies, no meta-analysis was attempted. In seven placebo-controlled trials of PPI therapy, the therapeutic gain for regurgitation response averaged 17% relative to placebo and was >20% less than that observed for heartburn. Studies comparing PPIs with histamine-2 receptor antagonists or prokinetics found the comparator drug response similar to the placebo response rates seen in the placebo-controlled trials.

CONCLUSIONS

The therapeutic gain with PPIs over placebo or comparator agents for the relief of regurgitation is modest, and considerably lower than for heartburn. Thus, regurgitation is likely to be an important factor for determining incomplete response to PPI treatment in GERD. Future trials would benefit from using regurgitation as a primary end point, applying an unambiguous definition of the symptom and of a positive treatment response, and using a validated patient-reported instrument for regurgitation assessment.

The added value of impedance-pH monitoring to Rome III criteria in distinguishing functional heartburn from non-erosive reflux disease

INTRODUCTION

Functional heartburn is defined by Rome III criteria as an endoscopy-negative condition with normal oesophageal acid exposure time, negative symptom association to acid reflux and unsatisfactory response to proton pump inhibitors. These criteria underestimated the role of non-acid reflux.

AIM

To assess the contribution of impedance-pH with symptom association probability (SAP) analysis in identifying endoscopy-negative patients with reflux disease and separating them from functional heartburn.

METHODS

Consecutive endoscopy-negative patients treated with proton pump inhibitors (n=219) undergoing impedance-pH monitoring off-therapy were analysed. Distal acid exposure time, reflux episodes, SAP and symptomatic response to proton pump inhibitors were measured.

RESULTS

Based on impedance-pH/SAP, 67 (31%) patients were pH+/SAP+, 6 (2%) pH+/SAP-, 83 (38%) hypersensitive oesophagus and 63 (29%) functional heartburn. According to pH-metry alone/response to proton pump inhibitors, 62 (28%) were pH+/SAP+, 11 (5%) pH+/SAP-, 61 (28%) hypersensitive oesophagus and 85 (39%) functional heartburn. In the normal-acid exposure population the contribution of impedance-pH/SAP compared to pH-metry alone/response to proton pump inhibitors in identifying patients with reflux disease and functional heartburn resulted to be 10%. In patients with abnormal-acid exposure, the contribution of impedance-pH/SAP increased by 3%.

CONCLUSION

Comparing impedance-pH testing with pH-metry alone plus the response to proton pump inhibitor therapy demonstrated that the latter ones cause underestimation of reflux disease patients and overestimation of functional heartburn patients.

Reflux parameters as modified by EsophyX or laparoscopic fundoplication in refractory GERD

BACKGROUND

EsophyX is a novel transoral incisionless fundoplication device developed to mimic surgical fundoplication. EsophyX fundoplication improves acid reflux parameters in proton pump inhibitor (PPI)-responsive GERD patients but its efficacy in refractory GERD has been scarcely studied.

AIM

To assess reflux parameters before and after EsophyX or laparoscopic fundoplication and their relationship with symptoms in refractory GERD.

METHODS

In an open-label study, we enrolled prospectively patients with heartburn/regurgitation persisting despite high-dose PPI therapy. Impedance-pH monitoring was performed on PPI therapy before intervention and off PPI therapy 3 months after intervention.

RESULTS

Ten patients chose to undergo EsophyX (EndoGastric Solutions, Redmond, WA, USA) fundoplication while ten chose laparoscopic fundoplication, and the baseline characteristics were comparable. Distal and proximal refluxes were significantly reduced post-operatively in the surgical but not in the endoscopic group and the median values were significantly lower in the former than in the latter. The oesophageal acid exposure time was normal in 50% of cases after EsophyX and in 100% of cases after surgery (P=0.033); the number of distal refluxes was normal in 20% and 90% of cases (P=0.005) and the number of proximal refluxes was normal in 40% and 100% of cases (P=0.011), respectively. A positive persisting symptom-reflux association was found post-operatively in 6/10 patients in the EsophyX group and in 0/10 patients in the surgical group (P=0.011).

CONCLUSIONS

In patients with refractory GERD, EsophyX fundoplication is significantly less effective than laparoscopic fundoplication in improving reflux parameters and accordingly, in inducing symptom remission.

The effect of antisecretory therapy and study duration on ambulatory esophageal pH monitoring

BACKGROUND

Conventional catheter-based and wireless pH monitoring continue to be widely used for the evaluation of GERD symptoms despite the emergence of pH-impedance monitoring.

GOALS

We sought to identify patient- and test-related factors predicting objective GERD parameters on catheter-based and wireless pH monitoring.

STUDY

Ambulatory pH studies in 2,067 subjects (50.4 ± 0.3 years, 66.3% female) were assessed for presenting symptoms, antireflux therapy status, test characteristics, distal esophageal total acid exposure time (AET), symptom index (SI), and symptom-reflux association (Ghillebert probability estimate, GPE). Univariate and multivariate logistic regression analyses were performed to identify predictors of GERD evidence, both off and on antireflux therapy.

RESULTS

Catheter-based pH monitoring was performed in 77.6%, and 90.1% of the studies were performed off antireflux therapy. The likelihood of finding GERD evidence was significantly higher off therapy (65.8 vs. 21.4% on therapy, p < 0.0001); this held true for both strong GERD evidence (elevated AET and positive GPE) and elevated AET alone. The SI did not complement AET and GPE. Extended pH recording with the wireless technique consistently increased diagnostic yield. On multivariate logistic regression, the status of antireflux therapy and frequency of symptoms dictated finding of GERD evidence, and yields were highest for perceptive symptoms (heartburn, chest pain, and cough).

CONCLUSIONS

Ambulatory pH testing off antireflux therapy improves detection of all degrees of GERD evidence. pH testing provides highest yields with frequent perceptive symptoms and least with isolated regurgitation and ENT symptoms. Extending pH-recording with wireless monitoring uniformly augments yield.

Reflux parameters as modified by laparoscopic fundoplication in 40 patients with heartburn/regurgitation persisting despite PPI therapy: a study using impedance-pH monitoring

BACKGROUND

Patients with typical reflux symptoms (heartburn/regurgitation) persisting despite proton pump inhibitor (PPI) therapy are not uncommon. Impedance-pH monitoring detects gastroesophageal reflux at all pH levels and may establish if ongoing symptoms on PPI therapy are associated with acid/nonacid reflux. Laparoscopic fundoplication is a therapeutic option in such patients but reflux parameters on PPI therapy and after intervention and their relationship with symptom persistence/remission have been scarcely studied.

AIMS

The aim of this study was to assess reflux parameters and their relationship with symptoms before and after laparoscopic fundoplication, on and off PPI therapy, respectively, in patients with PPI-unresponsive heartburn/regurgitation and with a positive symptom-reflux association and/or abnormal reflux parameters detected on PPI therapy.

METHODS

Impedance-pH monitoring was performed on high-dose PPI therapy and 3 months after laparoscopic fundoplication, off PPI therapy, in 40 patients with PPI-unresponsive heartburn/regurgitation. Symptoms were scored by a validated questionnaire.

RESULTS

Esophageal acid exposure time as well as the number of total and proximal reflux events and of acid and weakly acidic refluxes decreased significantly after surgery: normal values were found in 100, 77, 95, 92 and 65% of cases, respectively. Weakly alkaline refluxes increased significantly postoperatively but neither before nor after intervention were associated with symptoms. All patients reported total/subtotal remission of heartburn/regurgitation 3 months after surgery.

CONCLUSIONS

Laparoscopic fundoplication improves acid and weakly acidic reflux parameters when compared with PPI therapy. This improvement justifies the very high post-surgical symptom remission rate that we observed. Prolonged follow-up is warranted but our findings strongly support the surgical option in PPI failures.

Does reflux monitoring with multichannel intraluminal impedance change clinical decision making?

OBJECTIVES

Multichannel intraluminal impedance with pH (pH-MII) has become the criterion standard test for the evaluation of gastroesophageal reflux disease, but it is not clear whether the results of this test change clinical decision making. The goal of the present study was to determine the differences in clinical decision making by attending physicians based on the pH probe results versus MII results.

METHODS

We conducted a prospective study in which physicians were initially given pH probe results and asked how they would change the patient's clinical management based on these results. Physicians were then given the MII results and asked how their management would change. Physicians then were asked whether they believed MII affected their clinical decision making overall.

RESULTS

pH probe results changed clinical management 40% of the time and MII results changed clinical management an additional 22% of the time. Clinical decision making was not influenced by the performance of pH-MII on or off acid suppression. The escalation of acid suppression therapy was the main management change that occurred based on the pH-MII results.

CONCLUSIONS

The addition of MII to the standard pH probe resulted in a change in management in approximately 25% of the patients, suggesting that there may be a role for pH-MII in clinical practice.

Computer analysis of 24-h esophageal impedance signals

OBJECTIVE

To assess the accuracy of newly developed software for detection of gastro-esophageal reflux episodes in ambulatory 24-h impedance tracings. MATERIAL AND METHODS. 24-h esophageal impedance recordings obtained from 60 consecutive patients with reflux symptoms were used in this study. The impedance tracings of the first 10 consecutive patients were analyzed manually by three investigators. Liquid-containing reflux episodes and their proximal extent were scored. A consensus between the three investigators was used as a gold standard. Computer analysis using dedicated software was performed, and the results were compared with the results of the consensus agreement. In addition, in order to assess the accuracy of symptom association analysis 24-h impedance tracings of all 60 patients were analyzed both manually by one investigator and using computer software. The number of reflux episodes and the results of symptom association analysis obtained by the human and computer analysis software were compared.

RESULTS

The consensus meeting resulted in a total of 625 reflux episodes. The mean sensitivity and the percentage of true-positives of analysis by individual investigators was 89±1% and 94±1%, respectively. Automated analysis had a sensitivity of 73±4% and a proportion of true-positive reflux episodes of 62±8%. Symptom association analysis performed by the computer and a human observer showed concordant results in 83% of the patients.

CONCLUSIONS

Although not as good as manual analysis by experts, computer analysis can be a helpful tool to identify reflux episodes and to assess the relationship between reflux episodes and symptoms.

Reflux monitoring: on or off therapy?

The role of esophageal pH (or impedance) monitoring in diagnosing gastroesophageal reflux disease (GERD) has evolved over the years. In the era of empiric therapy with potent acid-suppressive agents such as proton pump inhibitors (PPIs), esophageal reflux monitoring is often reserved for patients with PPI-refractory symptoms (1, 2). Given the complexity of patient presentations, technological advancement, and emerging data in the field of GERD, two essential questions need to be addressed: (i) What are the indications for esophageal pH testing in patients suspected to have GERD? (ii) If patients do not respond to aggressive acid suppression, what is the likelihood that they still have reflux; and should the testing be performed at baseline (i.e., off therapy), or is it more important to know whether there is continued reflux despite therapy (i.e., on therapy)?

Esophageal impedance monitoring for gastroesophageal reflux

Dual pH-multichannel intraluminal impedance (pH-MII) is a sensitive tool for evaluating overall gastroesophageal reflux disease, and particularly for permitting detection of nonacid reflux events. pH-MII technology is especially useful in the postprandial period or at other times when gastric contents are nonacidic.pH-MII was recently recognized by the North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition and the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition as being superior to pH monitoring alone for evaluation of the temporal relation between symptoms and gastroesophageal reflux. In children, pH-MII is useful to correlate symptoms with reflux (particularly nonacid reflux), to quantify reflux during tube feedings and the postprandial period, and to assess efficacy of antireflux therapy. This clinical review is simply an evidence-based overview addressing the indications, limitations, and recommended protocol for the clinical use of pH-MII in children.

Diagnosis and initial management of gastroesophageal complications

Chronic esophageal exposure to reflux of gastroduodenal contents can result in complications of GERD including esophageal stricture, Barrett's oesophagus or extraesophageal symptoms such as laryngitis, chronic cough or asthma. Endoscopy is the main diagnostic tool for patients with chronic reflux presenting with dysphagia to visualise esophageal mucosa and identify the underlying pathology. Barrett's oesophagus should be suspected in those with chronic reflux disease. Patients with Barrett's oesophagus should undergo surveillance endoscopy in order to risk stratify to dysplasia or adenocarcinoma. New endoscopic ablative therapies in patients with Barrett's oesophagus and high grade dysplasia are promising new treatment modality for those who may not be candidates for definitive intervention. Given poor sensitivity of diagnostic tests in extraesophageal reflux, empiric therapy with proton pump patients is the initial recommended approach. Diagnostic testing with esophagogastroduodenoscopy and ambulatory pH and impedance monitoring is usually reserved for those unresponsive to acid suppressive therapy. Many uncertainties remain in this group of patients including which patient subgroups might benefit from acid suppressive therapy. Future outcome studies are needed to assess the role of impedance/pH monitoring in this group of patients and to determine who might symptomatically benefit from medical or surgical intervention.

Exertional esophageal pH-metry and manometry in recurrent chest pain

AIM: To investigate the diagnostic efficacy of 24-h and exertional esophageal pH-metry and manometry in patients with recurrent chest pain.

METHODS: The study included 111 patients (54% male) with recurrent angina-like chest pain, non-responsive to therapy with proton pump inhibitors. Sixty-five (59%) had non-obstructive lesions in coronary artery angiography, and in 46 (41%) significant coronary artery narrowing was found. In all patients, 24-h esophageal pH-metry and manometry, and treadmill stress tests with simultaneous esophageal pH-metry and manometry monitoring were performed. During a 24-h examination the percentage of spontaneous chest pain (sCP) episodes associated with acid reflux or dysmotility (symptom index, SI) was calculated. Patients with SI > 50% for acid gastroesophageal reflux (GER) were classified as having GER-related sCP. The remaining symptomatic individuals were determined as having non-GER-related sCP. During the stress test, the occurrence of chest pain, episodes of esophageal acidification (pH < 4 for 10 s) and esophageal spasm with more than 55% of simultaneous contractions (exercise-provoked esophageal spasm or EPES) were noted.

RESULTS: Sixty-eight (61%) individuals reported sCP during 24-h esophageal function monitoring. Eleven of these (16%) were classified as having GER-related sCP and 53/68 (84%) as having non-GER-related sCP. The exercise-provoked chest pain during a stress test occurred in 13/111 (12%) subjects. In order to compare the clinical usefulness of 24-h esophageal function monitoring and its examination limited only to the treadmill stress test, the standard parameters of diagnostic test evaluation were determined. The occurrence of GER-related or non-GER-related sCP was assumed as a “gold standard”. Afterwards, accuracy, sensitivity and specificity were calculated. These parameters expressed a prediction of GER-related or non-GER-related sCP occurrence by the presence of chest pain, esophageal acidification and EPES. Accuracy, sensitivity and specificity of chest pain during the stress test predicting any sCP occurrence were 28%, 35% and 80%, respectively, predicting GER-related sCP were 42%, 0% and 83%, respectively, and predicting non-GER-related sCP were 57%, 36% and 83%, respectively. Similar values were obtained for exercise-related acidification with pH < 4 longer than 10 s in the prediction of GER-related sCP (44%, 36% and 92%, respectively) and EPES in relation to non-GER-related sCP (48%, 23% and 84%, respectively).

CONCLUSION: The presence of chest pain, esophageal acidification and EPES had greater than 80% specificity to exclude the GER-related and non-GER-related causes of recurrent chest pain.

Advances in diagnostic testing for gastroesophageal reflux disease

Gastroesophageal reflux disease (GERD) contributes substantially to morbidity and to costs in the United States health care system. The burden of this disease has resulted in attempts at improving diagnosis and characterizing patients. Numerous research and technical advances have enhanced our understanding of both the utility and limitations of a variety of diagnostic modalities. The purpose of this review is to highlight recent advances in GERD diagnostic testing and to discuss their implications for use in clinical practice. Topics addressed include esophageal pH monitoring, impedance testing, symptom association analyses, narrow-band imaging, and histopathology.

Systematic review: role of acid, weakly acidic and weakly alkaline reflux in gastro-oesophageal reflux disease

BACKGROUND

The importance of weakly acidic and weakly alkaline reflux in gastro-oesophageal reflux disease (GERD) is gaining recognition.

AIM

To quantify the proportions of reflux episodes that are acidic (pH <4), weakly acidic (pH 4-7) and weakly alkaline (pH >7) in adult patients with GERD, and to evaluate their correlation with symptoms.

METHODS

Studies were identified by systematic PubMed and Embase searches. Data are presented as sample-size weighted means and 95% confidence intervals.

RESULTS

In patients with GERD taking a proton pump inhibitor (PPI), 80% (76-84%) of reflux episodes were weakly acidic or weakly alkaline and 83% (78-88%) of reflux symptom episodes were associated with weakly acidic or weakly alkaline reflux episodes. In patients with GERD not taking a PPI, 63% (59-67%) of reflux episodes were acidic and 72% (57-87%) of reflux symptom episodes were associated with acid reflux episodes. Six studies presented data separately for weakly alkaline reflux, which accounted for <5% of all reflux episodes, both on and off PPI therapy.

CONCLUSIONS

Weakly acidic reflux underlies the majority of reflux episodes in patients with GERD on PPI therapy, and is the main cause of reflux symptoms occurring despite PPI therapy.

The diagnosis of gastroesophageal reflux disease

BACKGROUND

Gastroesophageal reflux disease is a highly prevalent condition that imposes a significant economic impact on the US health care system. The utility of commonly used tests for the diagnosis of gastroesophageal reflux disease has not been adequately reviewed.

METHODS

A comprehensive review of the literature was undertaken to provide an evidence-based approach to the diagnosis of gastroesophageal reflux disease. EMBASE (1980-December 2008), OVID MEDLINE, and PubMed, (1966-December 2008) were searched using "gastroesophageal reflux" and "adults" with other terms, including medications, diagnostic tests, symptoms, and epidemiologic terms. Studies were limited to human trials, English language, and full articles.

RESULTS

Heartburn is a reasonably sensitive symptom for the diagnosis of gastroesophageal reflux disease, although it does not reliably predict esophagitis. Standardized questionnaires have limited specificity, whereas the double-contrast barium swallow has a low sensitivity to diagnose gastroesophageal reflux. The role of esophageal manometry is limited to accurate placement of a pH-measuring device. pH testing has reasonable sensitivity and specificity for the diagnosis of gastroesophageal reflux disease. The sensitivity of upper endoscopy to diagnose gastroesophageal reflux is lower than that of pH tests.

CONCLUSION

The diagnosis of gastroesophageal reflux disease remains difficult. In the absence of alarm symptoms, empiric treatment with acid suppression is warranted. pH testing provides valuable information in many patients, although the clinical utility of newer tests needs to be determined. Endoscopy should not be the first test used to diagnose gastroesophageal reflux.

Management of gastroesophageal reflux disease that does not respond well to proton pump inhibitors

PURPOSE OF REVIEW

Patients with gastroesophageal reflux disease (GERD) who are not responding to proton pump inhibitors (PPIs) given once daily are very common. These therapy-resistant patients have become the new face of GERD in clinical practice in the last decade and presently pose a significant therapeutic challenge to the practicing physician. We reviewed newly accumulated information about the management of PPI failure that has been published over the past 2 years.

RECENT FINDINGS

There are diverse mechanisms that contribute to the failure of PPI treatment in GERD patients and they are not limited to residual reflux. Some of the causes of PPI failure may coincide in the same patient. Upper endoscopy appears to have limited diagnostic value. In contrast, esophageal impedance with pH testing on therapy appears to provide the most insightful information about the subsequent management of these patients. Commonly, doubling the PPI dose or switching to another PPI will be offered to patients who failed PPI once daily. Failure of such therapeutic strategies is commonly followed by assessment for residual reflux. There is growing information about the potential value of compounds that can reduce transient lower esophageal sphincter relaxations. Esophageal pain modulators are commonly offered to patients with functional heartburn, although supportive clinical studies are still missing.

SUMMARY

Management of refractory GERD patients remains an important clinical challenge. Recent studies have cemented the value of impedance-pH testing in pursuing proper treatment. Presently, the most promising therapeutic development for this patient population is transient lower esophageal sphincter relaxation reducers.

Upper GI tract findings in patients with heartburn in whom proton pump inhibitor treatment failed versus those not receiving antireflux treatment

BACKGROUND

Failure of proton pump inhibitor (PPI) treatment in patients with heartburn is very common. Because endoscopy is easily accessible, it is commonly used as the first evaluative tool in these patients.

OBJECTIVE

To compare GERD-related endoscopic and histologic findings in patients with heartburn in whom once-daily PPI therapy failed versus those not receiving antireflux treatment.

DESIGN

Cross-sectional study.

SETTING

A Veterans Affairs hospital.

PATIENTS

Heartburn patients from the GI outpatient clinic.

INTERVENTION

Recording of endoscopic results.

MAIN OUTCOME MEASUREMENTS

Endoscopic findings and association between PPI treatment failure and esophageal mucosal injury by using logistic regression models.

RESULTS

A total of 105 subjects (mean age 54.7 +/- 15.7 years; 71 men, 34 women) were enrolled in the PPI treatment failure group and 91 (mean age 53.4 +/- 15.8 years; 68 men, 23 women) were enrolled in the no-treatment group (P = not significant). Anatomic findings during upper endoscopy were significantly more common in the no-treatment group compared with the PPI treatment failure group (55.2% vs 40.7%, respectively; P = .04). GERD-related findings were significantly more common in the no-treatment group compared with the PPI treatment failure group (erosive esophagitis: 30.8% vs 6.7%, respectively; P < .05). Eosinophilic esophagitis was found in only 0.9% of PPI treatment failure patients. PPI treatment failure was associated with a significantly decreased odds ratio of erosive esophagitis compared with no treatment, adjusted for age, sex, and body mass index (adjusted odds ratio 0.11; 95% CI, 0.04-0.30).

CONCLUSIONS

Heartburn patients in whom once-daily PPI treatment failed demonstrated a paucity of GERD-related findings compared with those receiving no treatment. Eosinophilic esophagitis was uncommon in PPI therapy failure patients. Upper endoscopy seems to have a very low diagnostic yield in this patient population.

The role of an alginate suspension on pepsin and bile acids - key aggressors in the gastric refluxate. Does this have implications for the treatment of gastro-oesophageal reflux disease?

OBJECTIVES

During a reflux event the oesophagus is exposed to a heterogeneous mixture of gastric juice components. The role of non-acid components of the refluxate in causing damage to the oesophagus is now well established but no therapeutic option exists to address this.

METHODS

The role of Gaviscon Advance (GA), a raft-forming alginate suspension, in protecting the oesophagus from damage by pepsin and bile acids (aggressors) was investigated using a series of in-vitro models.

KEY FINDINGS

GA was able to dose-dependently inhibit pepsin activity over and above the neutralisation effect of the formulation. This was evident against both protein and collagen substrates using two distinct colorimetric assays. GA was able to retard the diffusion of pepsin and multiple bile acids using a Franz cell model. Using the raft-forming mode of action GA was able to remove both pepsin and multiple bile acids from a simulated reflux event. There was capacity in the GA raft to accommodate aggressors from multiple reflux events.

CONCLUSIONS

GA can specifically remove both pepsin and bile acids from the refluxate, limit their diffusion and affect enzymatic activity of pepsin. There is a role for GA to reduce the damaging potential of the refluxate and thus protect the oesophagus.

Reflux patterns in patients with short-segment Barrett's oesophagus: a study using impedance-pH monitoring off and on proton pump inhibitor therapy

BACKGROUND

In short-segment Barrett's oesophagus (SSBO) heartburn may be absent and oesophageal acid exposure time (OAET) assessed with pH-only monitoring may be normal. By detecting reflux episodes independently of their acidity, multichannel intraluminal impedance-pH (MII-pH) monitoring allows a comprehensive characterization of reflux events, either off or on proton pump inhibitor (PPI) therapy.

AIM

To assess reflux parameters by MII-pH monitoring in newly diagnosed SSBO, at baseline and as modified with PPI therapy.

METHODS

Short-segment Barrett's oesophagus was defined by oesophageal intestinal metaplasia up to 3 cm in length. 24-h MII-pH monitoring was performed before and during PPI therapy.

RESULTS

Fifty patients were studied prospectively. Normal OAET was found at baseline in 15 patients (30%), 8 and 2 of whom with a higher than normal number of acid and weakly acidic refluxes, respectively. Overall, abnormal reflux parameters were detected by MII-pH monitoring in 90% of patients. Reflux events were prevalent in the upright period. On PPI therapy, acid refluxes decreased and a correspondent increase in weakly acidic refluxes was observed (median from 48.5 to 9 and from 16 to 57.5, respectively) (P < 0.001).

CONCLUSIONS

Acid refluxes, mainly in the upright period, characterize SSBO. PPI therapy transforms acid refluxes into weakly acidic refluxes.